Difference between revisions of "Biological Cognitive Enhancement"

From Lesswrongwiki
Jump to: navigation, search
(Created page with "'''Biological Cognitive Enhancement''' refers to a method of improving intelligence through the use of drugs such as methylphenidate (Ritalin) or dextroamphetamine (Adderall). Th...")
 
Line 1: Line 1:
'''Biological Cognitive Enhancement''' refers to a method of improving intelligence through the use of drugs such as methylphenidate (Ritalin) or dextroamphetamine (Adderall). These drugs are currently only available on prescription for the treatment of conditions such as ADHD or depression. However, there have been increasing reports of students obtaining drugs through other means. According to Elizabeth Smith and Martha Farah the exact effects of these stimulants on healthy individuals are yet to be known, but there does appear to be an improvement in the consolidation of memories and with the focus of concentration.
+
'''Biological Cognitive Enhancement''' is any modification in the biology of a person which increases his cognitive capacities <ref name="human capacities"> SAVULESCU, J. e MEULEN, Rudd ter (orgs.) (2011) "Enhancing Human Capacities". Wiley-Blackwell.  </ref>.  These modifications can be done through the use of drugs (‘smart pills’) or magnetic stimulation. The most imminent, successful and polemic method is through the use of drugs, substances that alter the functioning of ours brains neurochemistry in order to improve certain aspects of cognition.  
 +
There is an increasing trend in the use of cognitive enhancement drugs among healthy individuals in schools and colleges<ref> KAPNER, E. (2003) "Recreational use of Ritalin on college campuses". InfoFactsResources – The Higher Education Center for Alcohol and Other Drug Prevention. Available at: www.edc.org/hec/pubs/factsheets/ritalin.pdf (accessed 4 Jan 2006). </ref> <ref> TETER, C.J. et al. (2005). "Prevalence and motives for illicit use of prescription stimulants in an undergraduate student sample", J Am Coll Health 53 (2005).</ref>. This means this kind of enhancement technology is already in use. The overall impact of a widespread use of these kinds of drugs could be enormous <ref name="3ways"> BOSTROM, NICK. (2008) "Three Ways to Advance Science" For Nature Podcast, 31 January 2008. Available at: http://www.nickbostrom.com/views/science.pdf </ref>. However, the whole set of ethical consequences is unknown and subject of on-going developments <ref name="human capacities" /> <ref> SANDBERG, Anders e LIAO, S.M., (2008) "The Normativity of Memory Modification", Neuroethics (2008), (1 2) 85-99.  </ref> <ref> SANBERG, Anders e SAVULESCU, Julian. (2008). "Neuroenhancement of Love and Marriage: The Chemicals Between Us." Neuroethics (2008) Vol. 1:31-44. </ref> <ref> BOSTROM, Nick e SAVULESCO, Julian. (orgs.), (2009) "Human Enhancement". Oxford University Press.  </ref> <ref> BOSTROM, Nick e SANDBERG,  Anders. (2006) "Converging Cognitive Enhancements", Annals of the New York Academy of Sciences, Vol. 1093.</ref> <ref name="heuristic"> SANDBERG, Nick e SANDBERG, Anders. (2009) "The Wisdom of Nature: an Evolutionary Heuristic for Human Enhancement"  in: BOSTROM, Nick e SAVULESCU, Julian(orgs.). Human Enhancement. Oxford University Press, EUA. </ref> <ref> BOSTROM, Nick e SANDBERG, Anders. (2009) "Cognitive Enhancement: Methods, Ethics, Regulatory Challenges", Science and Engineering Ethics, Vol. 15, No. 3.</ref>
  
Aside from the possibility of side-effects, some observers such as [[Nick Bostrom]] feel there are also ethical issues that need to be addressed. He argues that these drugs may become a “must have” commodity in order to compete within an academic or work environment. What impact would such drugs have on an individuals personality? You may become a more effective office worker, but lose some charming character trait.
+
==Examples==
 +
Currently, there are several drugs been used as cognitive enhancers by healthy individuals, e.g.: caffeine, ritalin, aderall, modafinil and Aricept.  Academic research accessing the risks and benefits of these drugs in the healthy individual have only began recently.  In addition, the results of those researches are vastly ignored by most of the concerned population.
 +
Three of the most used, promising and known cognitive enhancement drugs are listed in more detail above:
 +
*Caffeine: Perhaps the most used and old cognitive enhancer. Caffeine has an excitatory result in the brain, by partially disabling the process of signaling low availability of energy. <ref name="squire"> SQUIRE, Larry R. et al. (orgs.) (2008) "Fundamental Neuroscience." Academic Press. 3a edition. </ref>. Caffeine and its metabolites also increase the serum concentration of adrenaline, increasing hear rate, blood pressure and stress <ref> DEWS, P.B. (1984). "Caffeine: Perspectives from Recent Research." Berlin: Springer-Valerag </ref>. Many researchers have found a vast number of beneficial cognitive effects, as improved concentration and memory retention <ref> BOLTON, Sanford (1981). "Caffeine: Psychological Effects, Use and Abuse". Orthomolecular Psychiatry 10 (3): 202–211. </ref>. Its beneficial effects on general health are also documented <ref> THOMPSON, Rebecca & KEENE, Karen (2004). "The pros and cons of caffeine". The Psychologist (The British Psychological Society) 17 (12): 698–701. </ref>. However, average medium dosages of an American adult male <ref> NCDT (2011). Report of the 2011 National Coffee Drinking Trends (NCDT).  </ref> <ref> ILLY, A. & VIVIANI, R. (1995) Espresso Coffee: The Chemistry of Quality.  San Diego: Academic P. </ref> surpasses the healthy dosage fourfold. At the averaged ingested dosage, caffeine have strong health detrimental health effects: increase risks of heart attacks and strokes  <ref> GREENBERG, J. A. Et al.(2007) "Caffeinated beverage intake and the risk of heart disease mortality in the elderly: a prospective analysis". Am J Clin Nutr 85 (2): 392–8. </ref> <ref> LESON. C. L. Et al. (1998) "Caffeine overdose in an adolescent male.". Journal of toxicology. Clinical toxicology Vol. 26 (5–6): 407–15. </ref> and addiction potential, with severe withdrawal symptoms: depression, irritability, pain and narcolepsy <ref> JULIANO, Laura M. & GRIFFITHS, Roland R. (2004) "A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features". Psychopharmacology 176 (1): 1–29. </ref>.
 +
*Modafinil:  Modafinil effects are mediated trough neurotransmitters histamine and dopamine. Histamine regulates the state of wakefulness. Dopamine has important roles in motivation, cognition, reward, attention and working memory <ref name="squire" />.  There are at least 7 studies on the cognitive enhancement properties of modafinil in healthy individuals <ref name="caid1"> CAIDWELL, John A. et al. (1999) "The Effects of Modafinil on Aviator Performance During 40 Hours of Continuous Wakefulness: A UH-60 Helicopter Simulator Study." Army aeromedical research unit fort rucker al. </ref> <ref name="caid2"> CAIDWELL, John A. et al. (2004) "The Efficacy of Modafinil for Sustaining Alertness and Simulator Flight Performance in F-117 Pilots During 37 Hours of Continuous Wakefulness." Air Force Research lab brooks AFB TX, Human effectiveness Dir/Biodynamics and protection div. </ref>  <ref name="li"> LI Yanfeng, ZHAN Hao, XIN Yimei, et al. (2007) "Effects of modafinil on vestibular function during 24 hour sleep deprivation". Frontiers of medicine in China, Vol. 1, Number 2, 226-229. </ref> <ref name="bara"> BARANSKI, J. V. Et al. (2004) "Effects of modafinil on cognitive and meta-cognitive performance".  Hum Psychopharmacol. 2004 Jul; Vol. 19(5):323-32. </ref> <ref name="mull1"> MÜLLER, U. Et al. (2004) "Effects of modafinil on working memory processes in humans". Psychopharmacology (Berl.) Vol. 177 (1-2): 161–9.  </ref>  <ref name="turn"> TURNER, D. C et al. (2003). "Cognitive enhancing effects of modafinil in healthy volunteers". Psychopharmacology (Berl.) Vol. 165 (3): 260–9. </ref>  <ref name="mull2"> MULLER, U. et all. (2012) "Effects of modafinil on non-verbal cognition, task enjoyment and creative thinking in healthy volunteers." Neuropharmocology: 2012 (In press).  </ref>. Those studies results were:
 +
** Enhanced performance on tests of digit span, visual pattern recognition memory, spatial planning and stop signal reaction time <ref name="turn" />.
 +
** Lower error rate in a visual spatial task<ref name="mull1"> </ref>.
 +
** Improved fatigue levels, motivation, reaction time and vigilance<ref name="bara" />.
 +
** Improvement on spatial working memory, planning and decision making at the most difficult levels, as well as visual pattern recognition memory following delay and subjective ratings of enjoyment of task performance <ref name="mull2" /> .
 +
** Decreased impairment in vestibular function in 24h sleep deprived individuals<ref name="li" />.
 +
** Decreased impairment on performance in a flight simulation test in 30h and 40h sleep deprived individuals<ref name="caid1" /> <ref name="caid2" />.
 +
** No adverse effects were reported in none of these studies, however this wasn't the target of any of these studies.
 +
[http://www.springerlink.com/content/?k=modafinil Many] [http://www.sciencedirect.com/science?_ob=ArticleListURL&_method=list&_ArticleListID=2100456952&_sort=r&_st=13&view=c&_acct=C000228598&_version=1&_urlVersion=0&_userid=10&md5=9facf727fff44b33bdd632f4e3f51852&searchtype=a other] studies in non-healthy patients have found some adverse effects<ref>http://www.rxlist.com/provigil-drug/side-effects-interactions.htm</ref>, but have confirmed its safety and - so far - no addiction potential profile. However, research on its long-term safety is deeply needed.
 +
*Aricept(Donepezil): Aricept inhibits the breakdown of acetylcholine. Acetylcholine is a neurotransmitter linked to long-term memory. There are at least two studies with healthy individuals that have found: greater memorization on how to perform a set of complex tasks <ref> YESAVAGE, et al. (2002). "Donepezil and flight simulator performance Effects on retention of complex skills" NEUROLOGY 2002; 59:123–125. </ref> and increased visual and verbal long-term memory <ref>  YESAVAGE, et al. (2002). "Donepezil and flight simulator performance Effects on retention of complex skills" NEUROLOGY 2002; 59:123–125. </ref>.  
  
==External Links==
+
==Biases affecting our judgment==
 +
There are several cognitive biases affecting our judgment on the risks and efficacy of biological cognitive enhancers. Two are worth mentioning:
 +
* Statistical format: we do not update ours beliefs correctly when presented with absolute probabilities (i.e.: 10%) - when the information is presented in terms of occurrences (i.e.: one person in ten) the belief update is much more close to [http://lesswrong.com/lw/1to/what_is_bayesianism/ bayesian] <ref> POHL, Rüdiger (orgs.). (2005) "Cognitive Illusions: A Handbook on Fallacies and Biases in Thinking, Judgement and Memory". Psychology Press. pp. 61-78 </ref>. This bias impairs our ability to use information from scientific research to update our beliefs. One can easily comprehend the risks involved with a certain drug if a friend suffered a heart attack due to its use, avoiding such drug from then on.  But reading an abstract number showing the rise in blood pressure – [http://www.who.int/healthinfo/global_burden_disease/GlobalHealthRisks_report_full.pdf the most important preventable risk factor for death] - of caffeine users is much higher than of modafinil users is too far away from the occurrence-based [http://wiki.lesswrong.com/wiki/Evolutionary_psychology savannah way] our brains are costumed to absorb information <ref> BUSS, David(orgs.). (2005) "The Handbook of Evolutionary Psychology". Wiley, New Jersey.  pp. 739-740. </ref>
 +
*Status quo:  a consistent and unjustified tendency to prefer that some parameter stays in the configuration it has always been, over other possible configurations. This tendency can manifest itself by preferring to continue to use a known drug with many side effects over a new safer drug and impair our judgment of many others technological advancements. When analyzing if a new configuration should be used, Bostrom  and Ord <ref> BOSTROM, Nick e ORD, Toby. (2006) "The Reversal Test: Eliminating Status Quo Bias in Applied Ethics". Ethics 116 (Julho 2006): 656-679. </ref> suggest the following heuristic: we imagine a scenario were the parameter will naturally change to the new configuration and ask if we would intervene. If so, then we would have a reason to think the new configuration should be preferred.
  
*[http://www.nickbostrom.com/cognitive.pdf Cognitive Enhancement: Methods, Ethics and Regulatory Challenges] by Nick Bostrom (2009)
+
==Relevance==
 +
Bostrom <ref name="3ways" /> argues for the huge impact of cognitive enhancements:
 +
"Imagine a researcher invented an inexpensive drug which was completely safe and which improved all‐round cognitive performance by just 1%. The gain would hardly be noticeable in a single individual. But if the 10 million scientists in the world all benefited from the drug the inventor would increase the rate of scientific progress by roughly the same amount as adding 100,000 new scientists. Each year the invention would amount to an indirect contribution equal to 100,000 times what the average scientist contributes. Even an Einstein or a Darwin at the peak of their powers could not make such a great impact. "
 +
Even outside the academic community, imagine a drug that improves the efficiency of all employees and workers around the world by just 1%. This would roughly means adding more 1 trillion dollars of production every year to the world gross product. This would be equivalent to the addition of an entire well developed country to the world, Germany for instance.
  
*[http://www.psych.upenn.edu/~mfarah/pdfs/PsychBullProof.pdf Are prescription stimulents “smart pills”?] by M. Elizabeth Smith and Martha Farah (2011)
+
==References==
 
+
{{Reflist|2}}
*[http://en.wikipedia.org/wiki/Methylphenidate Ritalin (Methylphenidate)] wikipedia
 
 
 
*[http://en.wikipedia.org/wiki/Adderall Adderall (dextroamphetamine)] wikipedia
 

Revision as of 10:31, 5 September 2012

Biological Cognitive Enhancement is any modification in the biology of a person which increases his cognitive capacities [1]. These modifications can be done through the use of drugs (‘smart pills’) or magnetic stimulation. The most imminent, successful and polemic method is through the use of drugs, substances that alter the functioning of ours brains neurochemistry in order to improve certain aspects of cognition. There is an increasing trend in the use of cognitive enhancement drugs among healthy individuals in schools and colleges[2] [3]. This means this kind of enhancement technology is already in use. The overall impact of a widespread use of these kinds of drugs could be enormous [4]. However, the whole set of ethical consequences is unknown and subject of on-going developments [1] [5] [6] [7] [8] [9] [10]

Examples

Currently, there are several drugs been used as cognitive enhancers by healthy individuals, e.g.: caffeine, ritalin, aderall, modafinil and Aricept. Academic research accessing the risks and benefits of these drugs in the healthy individual have only began recently. In addition, the results of those researches are vastly ignored by most of the concerned population. Three of the most used, promising and known cognitive enhancement drugs are listed in more detail above:

  • Caffeine: Perhaps the most used and old cognitive enhancer. Caffeine has an excitatory result in the brain, by partially disabling the process of signaling low availability of energy. [11]. Caffeine and its metabolites also increase the serum concentration of adrenaline, increasing hear rate, blood pressure and stress [12]. Many researchers have found a vast number of beneficial cognitive effects, as improved concentration and memory retention [13]. Its beneficial effects on general health are also documented [14]. However, average medium dosages of an American adult male [15] [16] surpasses the healthy dosage fourfold. At the averaged ingested dosage, caffeine have strong health detrimental health effects: increase risks of heart attacks and strokes [17] [18] and addiction potential, with severe withdrawal symptoms: depression, irritability, pain and narcolepsy [19].
  • Modafinil: Modafinil effects are mediated trough neurotransmitters histamine and dopamine. Histamine regulates the state of wakefulness. Dopamine has important roles in motivation, cognition, reward, attention and working memory [11]. There are at least 7 studies on the cognitive enhancement properties of modafinil in healthy individuals [20] [21] [22] [23] [24] [25] [26]. Those studies results were:
    • Enhanced performance on tests of digit span, visual pattern recognition memory, spatial planning and stop signal reaction time [25].
    • Lower error rate in a visual spatial task[24].
    • Improved fatigue levels, motivation, reaction time and vigilance[23].
    • Improvement on spatial working memory, planning and decision making at the most difficult levels, as well as visual pattern recognition memory following delay and subjective ratings of enjoyment of task performance [26] .
    • Decreased impairment in vestibular function in 24h sleep deprived individuals[22].
    • Decreased impairment on performance in a flight simulation test in 30h and 40h sleep deprived individuals[20] [21].
    • No adverse effects were reported in none of these studies, however this wasn't the target of any of these studies.

Many other studies in non-healthy patients have found some adverse effects[27], but have confirmed its safety and - so far - no addiction potential profile. However, research on its long-term safety is deeply needed.

  • Aricept(Donepezil): Aricept inhibits the breakdown of acetylcholine. Acetylcholine is a neurotransmitter linked to long-term memory. There are at least two studies with healthy individuals that have found: greater memorization on how to perform a set of complex tasks [28] and increased visual and verbal long-term memory [29].

Biases affecting our judgment

There are several cognitive biases affecting our judgment on the risks and efficacy of biological cognitive enhancers. Two are worth mentioning:

  • Statistical format: we do not update ours beliefs correctly when presented with absolute probabilities (i.e.: 10%) - when the information is presented in terms of occurrences (i.e.: one person in ten) the belief update is much more close to bayesian [30]. This bias impairs our ability to use information from scientific research to update our beliefs. One can easily comprehend the risks involved with a certain drug if a friend suffered a heart attack due to its use, avoiding such drug from then on. But reading an abstract number showing the rise in blood pressure – the most important preventable risk factor for death - of caffeine users is much higher than of modafinil users is too far away from the occurrence-based savannah way our brains are costumed to absorb information [31]
  • Status quo: a consistent and unjustified tendency to prefer that some parameter stays in the configuration it has always been, over other possible configurations. This tendency can manifest itself by preferring to continue to use a known drug with many side effects over a new safer drug and impair our judgment of many others technological advancements. When analyzing if a new configuration should be used, Bostrom and Ord [32] suggest the following heuristic: we imagine a scenario were the parameter will naturally change to the new configuration and ask if we would intervene. If so, then we would have a reason to think the new configuration should be preferred.

Relevance

Bostrom [4] argues for the huge impact of cognitive enhancements: "Imagine a researcher invented an inexpensive drug which was completely safe and which improved all‐round cognitive performance by just 1%. The gain would hardly be noticeable in a single individual. But if the 10 million scientists in the world all benefited from the drug the inventor would increase the rate of scientific progress by roughly the same amount as adding 100,000 new scientists. Each year the invention would amount to an indirect contribution equal to 100,000 times what the average scientist contributes. Even an Einstein or a Darwin at the peak of their powers could not make such a great impact. " Even outside the academic community, imagine a drug that improves the efficiency of all employees and workers around the world by just 1%. This would roughly means adding more 1 trillion dollars of production every year to the world gross product. This would be equivalent to the addition of an entire well developed country to the world, Germany for instance.

References

  1. 1.0 1.1 SAVULESCU, J. e MEULEN, Rudd ter (orgs.) (2011) "Enhancing Human Capacities". Wiley-Blackwell.
  2. KAPNER, E. (2003) "Recreational use of Ritalin on college campuses". InfoFactsResources – The Higher Education Center for Alcohol and Other Drug Prevention. Available at: www.edc.org/hec/pubs/factsheets/ritalin.pdf (accessed 4 Jan 2006).
  3. TETER, C.J. et al. (2005). "Prevalence and motives for illicit use of prescription stimulants in an undergraduate student sample", J Am Coll Health 53 (2005).
  4. 4.0 4.1 BOSTROM, NICK. (2008) "Three Ways to Advance Science" For Nature Podcast, 31 January 2008. Available at: http://www.nickbostrom.com/views/science.pdf
  5. SANDBERG, Anders e LIAO, S.M., (2008) "The Normativity of Memory Modification", Neuroethics (2008), (1 2) 85-99.
  6. SANBERG, Anders e SAVULESCU, Julian. (2008). "Neuroenhancement of Love and Marriage: The Chemicals Between Us." Neuroethics (2008) Vol. 1:31-44.
  7. BOSTROM, Nick e SAVULESCO, Julian. (orgs.), (2009) "Human Enhancement". Oxford University Press.
  8. BOSTROM, Nick e SANDBERG, Anders. (2006) "Converging Cognitive Enhancements", Annals of the New York Academy of Sciences, Vol. 1093.
  9. SANDBERG, Nick e SANDBERG, Anders. (2009) "The Wisdom of Nature: an Evolutionary Heuristic for Human Enhancement" in: BOSTROM, Nick e SAVULESCU, Julian(orgs.). Human Enhancement. Oxford University Press, EUA.
  10. BOSTROM, Nick e SANDBERG, Anders. (2009) "Cognitive Enhancement: Methods, Ethics, Regulatory Challenges", Science and Engineering Ethics, Vol. 15, No. 3.
  11. 11.0 11.1 SQUIRE, Larry R. et al. (orgs.) (2008) "Fundamental Neuroscience." Academic Press. 3a edition.
  12. DEWS, P.B. (1984). "Caffeine: Perspectives from Recent Research." Berlin: Springer-Valerag
  13. BOLTON, Sanford (1981). "Caffeine: Psychological Effects, Use and Abuse". Orthomolecular Psychiatry 10 (3): 202–211.
  14. THOMPSON, Rebecca & KEENE, Karen (2004). "The pros and cons of caffeine". The Psychologist (The British Psychological Society) 17 (12): 698–701.
  15. NCDT (2011). Report of the 2011 National Coffee Drinking Trends (NCDT).
  16. ILLY, A. & VIVIANI, R. (1995) Espresso Coffee: The Chemistry of Quality. San Diego: Academic P.
  17. GREENBERG, J. A. Et al.(2007) "Caffeinated beverage intake and the risk of heart disease mortality in the elderly: a prospective analysis". Am J Clin Nutr 85 (2): 392–8.
  18. LESON. C. L. Et al. (1998) "Caffeine overdose in an adolescent male.". Journal of toxicology. Clinical toxicology Vol. 26 (5–6): 407–15.
  19. JULIANO, Laura M. & GRIFFITHS, Roland R. (2004) "A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features". Psychopharmacology 176 (1): 1–29.
  20. 20.0 20.1 CAIDWELL, John A. et al. (1999) "The Effects of Modafinil on Aviator Performance During 40 Hours of Continuous Wakefulness: A UH-60 Helicopter Simulator Study." Army aeromedical research unit fort rucker al.
  21. 21.0 21.1 CAIDWELL, John A. et al. (2004) "The Efficacy of Modafinil for Sustaining Alertness and Simulator Flight Performance in F-117 Pilots During 37 Hours of Continuous Wakefulness." Air Force Research lab brooks AFB TX, Human effectiveness Dir/Biodynamics and protection div.
  22. 22.0 22.1 LI Yanfeng, ZHAN Hao, XIN Yimei, et al. (2007) "Effects of modafinil on vestibular function during 24 hour sleep deprivation". Frontiers of medicine in China, Vol. 1, Number 2, 226-229.
  23. 23.0 23.1 BARANSKI, J. V. Et al. (2004) "Effects of modafinil on cognitive and meta-cognitive performance". Hum Psychopharmacol. 2004 Jul; Vol. 19(5):323-32.
  24. 24.0 24.1 MÜLLER, U. Et al. (2004) "Effects of modafinil on working memory processes in humans". Psychopharmacology (Berl.) Vol. 177 (1-2): 161–9. Cite error: Invalid <ref> tag; name "mull1" defined multiple times with different content
  25. 25.0 25.1 TURNER, D. C et al. (2003). "Cognitive enhancing effects of modafinil in healthy volunteers". Psychopharmacology (Berl.) Vol. 165 (3): 260–9.
  26. 26.0 26.1 MULLER, U. et all. (2012) "Effects of modafinil on non-verbal cognition, task enjoyment and creative thinking in healthy volunteers." Neuropharmocology: 2012 (In press).
  27. http://www.rxlist.com/provigil-drug/side-effects-interactions.htm
  28. YESAVAGE, et al. (2002). "Donepezil and flight simulator performance Effects on retention of complex skills" NEUROLOGY 2002; 59:123–125.
  29. YESAVAGE, et al. (2002). "Donepezil and flight simulator performance Effects on retention of complex skills" NEUROLOGY 2002; 59:123–125.
  30. POHL, Rüdiger (orgs.). (2005) "Cognitive Illusions: A Handbook on Fallacies and Biases in Thinking, Judgement and Memory". Psychology Press. pp. 61-78
  31. BUSS, David(orgs.). (2005) "The Handbook of Evolutionary Psychology". Wiley, New Jersey. pp. 739-740.
  32. BOSTROM, Nick e ORD, Toby. (2006) "The Reversal Test: Eliminating Status Quo Bias in Applied Ethics". Ethics 116 (Julho 2006): 656-679.